Disabling cpuspeed under SuSE/RHEL4/CentOS 4.X to maintain system stability
By default, SuSE Linux, Red Hat Enterprise Linux 4 and CentOS 4.X enable the cpuspeed tool. Cpuspeed changes the processor clock speed dynamically depending on the system load. Slower clock speed is utilized when the system is idle or under light load. This is the Opteron Cool n Quiet feature.
However, cpuspeed is not SMP safe due to a "clock skew" issue where system time is not kept correctly. This results in system lockups and crashes. Thus it is necessary to disable cpuspeed (default setting at the factory).
If the operating system has been reinstalled, run 'chkconfig cpuspeed off' to disable cpuspeed under Red Hat Enterprise Linux 4 and CentOS 4.X.
To disable cpuspeed under SLES9, edit /etc/sysconfig/powersave/common and set the value of POWERSAVE_CPUFREQD_MODULE to off. Afterward, reboot the server.
To disable cpuspeed under SuSE Linux Professional 9.x or 10.x, run yast. Next select System, System Services (Runlevel) and disable powersaved. Afterward, reboot the server.
Note: Cpuspeed is only functional if the BIOS Cool n Quiet feature is enabled. If Cool n Quiet has been disabled in the BIOS, running cpuspeed yield no result.
In BIOS VE1.05, Cool n Quiet can be enabled or disabled (default setting at the factory). In BIOS VE1.02, Cool n Quiet is enabled automatically and there is no option to disable it.
Affected models
All dual processor and quad processor Opteron models